When Congress cracked down on Internet gambling last year, Michael Clebnik was poised to profit. The 48-year-old entrepreneur from Newton had recently launched a poker site with a business model that didn’t depend on gambling.

“We looked at the dynamic of poker content and [were confident] there was a different way to be able to offer this to the US audience,” said Clebnik, chief executive of Framingham-based Power Play Development.

Clebnik said his company began working on the no-money-down platform, called the National League of Poker, in late 2004. The site – nlop.com – launched in June 2006, four months before Congress enacted the Unlawful Internet Gambling Enforcement Act that was created to stop offshore poker sites from capitalizing on foreign market exchanges.

Nearly all online poker that was publicly traded on the London exchange closed its virtual doors soon after the law passed, shutting more than 23 million Americans out of the game, according to John A. Pappas, executive director of The Poker Players Alliance in Washington, D.C.

Many players seeking a new online game seem to be finding their way to Clebnik’s site. In October 2006, the site had just over 30,000 registered players, according to Clebnik. In April, it reached 85,000, and today it has 152,000 with a new registration every 4½ minutes. Sixty-nine percent of the site members are male.

Clebnik makes his money by running ads that are tailored to individual player’s demographics. Clebnik reaps more cash if visitors click onto an ad to view a sponsor site, answer surveys, or purchase a product.

“What’s interesting about poker is that it engages people for very long user sessions,” said Clebnik. Players on his site, he says, spend an average of 55 minutes per session.

The company steers clear of problems with the antigambling law by not accepting money from players. Instead, it operates point-based competitions and runs weekly leader boards. Each month the National League of Poker guarantees $25,000 will be paid out in cash and prizes including trips, electronics, sponsor specials, and seats at the World Series of Poker in Las Vegas

Last month the league mailed to more than 3,000 people checks ranging from $5 to $500 – leaving plenty of room for profit.

“On average we’ve been generating an excess of $125,000 a month,” said Clebnik.

He’s projecting his numbers will increase in 2008 as he upgrades the site and begins to focus on promoting it.

David Marshall, a 23-year-old poker enthusiast from Oxford, Maine, says he spends an average of 20 hours a week on Clebnik’s site. Currently in plumbers-and-pipe-fitters school and working construction, Marshall won a coveted seat ($1,500 value) at the World Series of Poker this past summer.

Marshall, who was knocked out of the tournament in the third round, admits that there have been times where he began playing poker at 9 p.m. and kept going until nine the next morning.

“When you’re running hot it’s hard to stop,” Marshall said.

Agawam resident Peter Hayes, a 46-year-old mill specialist at Home Depot, also won a seat at the 2007 World Series of Poker, but was knocked out three hours into the first day. Hayes said that although he has never purchased anything advertised on the National League of Poker site, he often clicks on the advertisements to pick up the bonus points that the league offers.

All players choose a screen name and are able to chat online during their hands. For some people, like 33-year-old Barry Silver of North Attleborough, it’s a way to incorporate a human touch.

“You run into the same people and come to know them though a chat, so when they return you can ask, ‘How are your kids – are they still sick?’ ” Silver said. “The games become a friendly battle.”

Silver, the chief technology officer for Security Lock Distributors in Westwood, often juggles parenting duties and playing at home, and once played through an entire night at work.

“I was at work and had to wait for the systems to update before I could test them,” Silver said. “It was amazing to see how many people were playing between 1 a.m. and 4 a.m.”

Clebnik said there are a number of companies who are now trying to run free-to-play sites supported by advertising, such as Prizewagon, Ujogo, and NoPayPOKER. Businesses like the Waltham-based GameLogic are harnessing the power of free-play poker to drive more repeat visits to casinos.

“Free games serve as a magnet for main club members,” said John E. Taylor Jr., president and chief executive of GameLogic. “Nearly 40 million people play games on the Internet each month at sites like Pogo, msngames, and AOLgames, to win sweepstakes entries, so we bolt on a game site to our casino clients’ existing websites.”

Taylor said that his company uses the draw of the games on casino websites to help them sign new members into brick-and-mortar players clubs. To obtain a players card and redeem prizes, prospective members must go into the casino with their license to verify age.

GameLogic works with clients such as Foxwoods, Newport Grand in Rhode Island, Dover Downs in Delaware, and others in Nevada and New Mexico.

“About 10 to 20 percent of on-property traffic will show up online, spending about 55 minutes on what we call fun play,” said Taylor.

Silver, who has also gotten his father involved on the National League of Poker site, said he plays at least three or four times a week. Since his house has wireless Internet access, he often starts in the family’s living room and puts down his laptop when one of his three children wants to play.

“Then I might move into the kitchen and talk with my wife – I can still interact with everyone while playing the game,” he said.

But every now and then, Silver admits he’ll get “the look” from his wife who will say, “Try to lose and wrap it up.”